1. Field of the Invention
The present invention relates generally to a mobile telecommunication terminal, and more particularly to a display interface of a mobile telecommunication terminal.
2. Discussion of the Related Art
FIG. 1 is a schematic view of a related art mobile telecommunication terminal. FIG. 2 is a schematic view of a related art liquid crystal display interface. FIG. 3 is a signal timing diagram according to the related art liquid crystal display interface.
Referring to FIG. 1, a folding type mobile telecommunication terminal 100 includes a main body 110 and a liquid crystal display (LCD) 120. Using a 16-bit bus, data is transmitted between the main body 110 and the LCD 120. Referring now to FIG. 2, the 16-bit bus includes a plurality of signal lines to control sixteen data lines used to transmit data. The control signals include a chip select (CS) signal, a write enable (WE) signal, an output enable (OE) signal, and an address (Add) signal. The CS signal is used to enable the LCD 120. The WE signal is used to write data from the main body 110 to the LCD 120. The OE signal is a read signal to read information from the main body 110. The Add signal is an address signal to select a color signal (i.e., red (R), green (G), and blue (B)) (color signal information). As described above, the 16-bit bus LCD interface requires twenty signal lines.
In the 16-bit bus, the color information (R, G, and B) in a pixel of an LCD is transmitted by n-bits in a digital form. Therefore, a data width of 3×n is required for the transmission. When the required data width exceeds 16 bits, the data is divided and transmitted by units of 16 bits. For example, when using an LCD screen displaying 256k colors, 6 bits for each color R, G, and B are allotted, thereby requiring a data width of 18 bits. The 18-bit packed data is divided into a 16-bit data packet and a 2-bit data packet, to be transmitted to the LCD through the bus using two cycles, as shown in FIG. 3.
Therefore, when a 16-bit bus is used, twenty signal lines, including a data signal and a control signal are required to transmit the data. In the folding type mobile telecommunication terminal, the LCD 120 is connected to the main body 110 by a hinge 130. The signal lines are connected to one another through a flexible printed circuit board (FPCB) 140. The width of the FPCB 140 is limited due to structural limitations of such a connection. Furthermore, folding type communication devices are frequently opened and closed, which applies structural stress to the FPCB 140.
In order to prevent a deficiency in the signal line from occurring, such as a break, the width of the signal line must be of at least some minimum width. In one such minimum pattern width, forty signal lines are used in the FPCB 140. The forty signal lines are used as signal lines between the main body 110 and the LCD 120, as well as to a receiver, a vibrating mechanism, a light emitting diode (LED), and a power source. Thus, additional signal lines are not available to perform other functions. Furthermore, by allotting a maximum number of signal lines into a limited width FPCB 140, the reliability of each signal line may be decreased.
In addition, as the functions of the recently introduced mobile telecommunication terminals are becoming more diverse, consumers need to open and close the hinge 130 more often. Consumers now also demand more sophisticated designs and structures for the hinge 130, such as those used in LCDs of camcorder type devices and slim type communication devices. Therefore, in order to satisfy these consumer demands, the width of the FPCB 140 needs to be reduced. However, since the 16-bit bus requires 20 signal lines, it is not possible to reduce the width of the FPCB 140.